[Background of the Invention]
(1) Technical field of the Invention
[0001] The present invention relates to a lens meter to measure optical characteristics
of eye glass lenses. More particularly, the invention relates to a lens meter which
is applicable to both eye glasses as ordinary products as well as test glasses having
trial frames.
(2) Related Art Statement
[0002] Heretofore, there have known lens meters for measuring the optical characteristics
of lenses assembled into eye glass units.
[0003] Such a lens meter comprises an eye glass support adapted for supporting the eye glass
unit at a given location such that lenses may be substantially horizontal, a light
source, such as an LED, adapted for emitting given inspection lights for the measurement
of the optical characteristics, light-projecting optical systems adapted for the inspection
lights emitted from the light sources to lenses of the eye glass unit supported by
the eye glass support almost in optical axis directions of the lenses, respectively,
a light detector such as a CCD, and detecting optical systems adapted for leading
transmitted lights of the inspection lights through the lenses of the eye glass unit
to the light detectors, respectively, wherein the light-projecting optical systems
lead the inspection lights emitted from the light sources to the lenses of the eye
glass unit supported by the eye glass support almost in the optical axes directions
of the lenses, respectively, the detection optical systems lead the transmitted lights
through the lenses of thee eye glass unit to the light detectors, respectively, and
the light detectors detect the light intensity distribution of the transmitted lights
to measure the optical characteristics of the eye glass unit, respectively.
[0004] Different from a meter device for measuring a single lens, the above lens meter is
adapted to measure the optical characteristics of the lenses assembled to an eye glass
frame in the form of the eye glass unit. Therefore, as shown in Fig. 21, the eye glass
support comprises two sandwiching members 21 and 22, which are displaceable nearer
or remoter relative to each other and are adapted to sandwich the outer edge of the
eye glass unit in cooperation with each other. The sandwiching members 21 and 22 sandwich
the outer edge of the frame in a case of a framed eye glass unit, whereas the sandwiching
members 21 and 22 sandwich the outer edges of the lenses in the case of a frame-less
eye glass unit. Thereby, the lenses of the eye glass unit are fixed at given locations
for measurement.
[0005] From the standpoint of the posture stability of the eye glasses when set, the eye
glass support including the sandwiching members 21 and 22 generally supports the eye
glass unit such that the lenses are substantially horizontal. In the lens meter 100
shown in Fig. 21, supporting pins 23 and 23 erected on an under side of the lenses
are adapted to support the under faces of the lenses. See JP-A 2002-202219, JP-A 2002-257680,
JP-A 2002-257681, JP-A 2002-296549 and JP-A 2003-194670.
[0006] The above-mentioned conventional lens meter is mainly used for measuring the optical
characteristics of the eye glass unit as a product. There is also a demand, however,
to measure the optical characteristics of detachable lenses 12 (See Fig. 13(b)) fitted
to a so-called trial frame 11 (See Fig. 13(a)) which is used for examination of visual
acuity, etc. before the product eye glass unit is produced. In this case, the inspection
glass unit consisting of the trial frame 11 and the detachable lenses 12 fitted to
the trial frame 11 needs to be supported by the glass unit support.
[0007] However, if the inspection glass unit 10 is set in the same manner as in the case
of the ordinary eye glass unit as a product, as shown in Fig. 22, the sandwiching
member 21 (or 22) may touch a tab 12c provided at the detachable lens 12 and turn
the detachable lens 12 together with the tab 12c relative to the frame 11.
[0008] When the detachable lens 12 is an astigma-correcting lens, the lens 12 is turned
to make an angle of a cylindrical axis 12 of the lens different from a set one, so
that the target optical characteristics cannot be measured.
[0009] Further, the eye glass unit is sandwiched by the sandwiching members 21, 22 such
that the lights passing the optical axes of the glasses of the eye glass unit are
inputted into almost the centers of the light detectors, respectively. However, even
if the detachable lens 12 of the inspection glass unit is not turned, it may be that
one of the sandwiching members, 21, holds the frame 11 via the tab 12c between the
other, and thus the optical axis 12d of the lens 12 is apart from the supporting pin
23 deposited at a location corresponding to almost the center of the optical detector,
by a distance L5 corresponding to a projected amount of the tab 12c from the frame
11. As a result, the light passing the optical axis 12d of the lens 12 is not inputted
into almost the center of the optical detector, so that measurement results may be
obtained at good precision.
Summary of the Invention
[0010] The present invention has been accomplished in view of the above circumstances, and
is to provide a lens meter which can measure optical characteristics of lenses readily
and at high precision for eye glass units as ordinary products and inspection eye
glass units having trial frames.
[0011] According to the lens meter of the present invention, the sandwiching members for
sandwiching and supporting the eye glass unit are provided with inspection eye glass
frame adaptors which prevent the sandwiching members or the like from butting the
tab of the detachable exchange type lens projecting from the inspection eye glass
frame such as the trial frame.
[0012] That is, the lens meter according to the present invention comprising a glass unit
support for supporting an eye glass unit such that glasses of the eye glass unit are
almost horizontal, light sources for emitting given inspection lights, respectively,
light-projecting optical systems for projecting inspection lights emitted from the
light sources upon the lenses of the eye glass unit supported by the glass unit support
substantially along optical axes of the lenses, respectively, light detectors, and
light-detecting optical systems for leading transmitted lights of the inspection lights
passing the lenses of the eye glass unit to the light detectors, respectively, said
glass unit support comprising two sandwiching members which are displaceable nearer
or apart from each other and adapted to sandwich an outer peripheral portion of the
eye glass unit in cooperation with each other, and inspection glass frame adaptors
being capable of being fitted to and detached from said two sandwiching members, respectively,
said inspection glass frame adaptors comprising projecting sandwiching portions, respectively,
which project toward the opposite sandwiching members, respectively, when the adaptors
are fitted to the sandwiching members, respectively, and which contact those portions
of the frame of the inspection glass unit other than movable areas of tabs of detachable
lenses projecting from a frame of an inspection glass lens unit supported by the glass
unit support as the eye glass unit, whereas those portions of the adaptors other than
the projecting sandwiching portions do not interfere with the movable areas of the
tabs, respectively.
[0013] The term "inspection glass unit" is used herein to mean not an eye glass unit as
a product consisting of a pair of eye glass lenses and their frame but a trial glass
unit in which one or more of numerous kinds of detachable lenses 12 having almost
the same size with different optical characteristics are fitted into a trial frame
(inspection glass frame) as shown in Fig. 13, for example. The inspection glass unit
is used for visual acuity test before the production of an eye glass unit as a product.
[0014] As shown in Fig. 13(b), the tab is a grip provided at a ring 12b for holding a lens
body 12a of the detachable lens 12 from an outer peripheral portion. The tab functions
not only as the grip but also as an indicator for showing front and rear sides and
a visual correction degree of the lens body 12a and an indicator for indicating a
standard position of the an angular degree of a cylindrical axis of an astigma-correcting
lens.
[0015] A movable area of the tab is a movable range in which the tab is movable when the
detachable lens 12 is fitted to the trial frame 11, not a locus range in which the
tab moves during attaching and detaching the detachable lens relative to the trial
frame. Therefore, since the lens 12 can be turned almost around the optical axis of
the lens 12 as its rotational axis relative to the trial frame 11 in the state that
the detachable lens 12 is fitted to the trial frame 11, the movable are of the tab
is a band-shaped circular arc range as the locus of the tab 11 as observed when the
lens 12 is turned around the rotatable range.
[0016] According to the lens meter of the present invention, when the optical characteristics
of the detachable lens fitted to the trial frame are to be measured, the frame of
the inspection glass unit can be sandwiched and held with the projecting sandwiching
portions of the inspection glass frame adaptors in the state that the adaptors are
fitted to the sandwiching members, respectively. In addition, since the adaptors do
not interface with the movable areas of the tabs of the detachable lenses fitted to
the trial frame of the inspection glass unit, the adaptors do not move the detachable
lenses when the adaptors sandwich the inspection glass unit. Thus, the optical characteristics
of the lenses can be measured at high precision, while the lenses maintain positional
relationship to the frame defined when the inspection glass unit is set to the lens
meter.
[0017] Since the adaptors do not contact the tabs, the measured results can be obtained
at high precision from the standpoint of preventing the optical axes of the inspection
glass lenses from largely deviating from almost the centers of the optical detectors,
respectively.
[0018] Further, since the adaptors are fitted to the sandwiching members of the lens meter,
not to the inspection glass unit, the adaptors can be attached and detached more easily
as compared with a case where such adaptors are fitted to the inspection glass unit.
The contents of Japanese patent application No. 2004-019131 and those of U.S.P.
6,778,264B2 are incorporated hereinto by reference to them.
[Brief Description of the Drawings]
[0019] For a better understanding of the invention, reference is made to the attached drawings,
wherein:
Fig. 1A is a perspective view of an appearance of a lens meter according to one embodiment
of the present invention showing a general construction thereof.
Fig. 1B is a figure showing an example of optical systems, etc. built in the lens
meter shown in Fig. 1A.
Fig. 2 is a schematic view showing an example of a monitor (No. 1) provided in the
lens meter shown in Fig. 1A
Fig. 3 is a schematic view showing an example of a monitor (No. 2) provided in the
lens meter shown in Fig. 1A.
Fig. 4 is a perspective view showing details of a setting section of the lens meter
shown in Fig. 1A.
Fig. 5 is a plane view showing an initial state in which a product eye glass unit
is set at the setting section shown in Fig. 4.
Figs. 6(a) and 6(b) are sectional views of Fig. 5 along with sectional lines A-A and
B-B, respectively.
Fig. 7 is a plane view showing a state in which the product eye glass unit placed
at the product eye glass unit is sandwiched.
Figs. 8(a) and 8(b) are sectional views of Fig. 7 along with sectional lines E-E and
F-F, respectively.
Figs. 9(a) and 9(b) are sectional views of Fig. 7 along with sectional lines E-E and
F-F, respectively, showing a finally sandwiched state.
Figs. 10(a) and 10(b) are sectional views of Fig. 5 along with sectional lines C-C
and D-D, respectively.
Figs. 11(a) and 11(b) are schematic views showing the construction and function of
a lift mechanism for a light-shielding member and a frame support (No. 1).
Figs. 12(a) and 12(b) are schematic views showing the construction and function of
the lift mechanism for the light-shielding member and the frame support (No. 2).
Figs. 13(a) and 13(b) are schematically showing an inspection eye glass unit, illustrating
a trial frame (inspection glass frame) and a detachable lens, respectively.
Figs. 14(a) and 14(b) are perspective views of inspection glass frame adaptors, illustrating
one for a rear sandwiching member and another for a front sandwiching member, respectively.
Fig. 15 is a perspective view showing a state in which inspection glass frame adaptors
are fitted to the sandwiching members, respectively.
Fig. 16 is a plane view showing a state in which the inspection glass unit is sandwiched
at the setting section shown in Fig. 15.
Figs. 17(a) and 17(b) are sectional views showing inspection glass frame adaptors
integrally attached to the sandwiching members, respectively.
Fig. 18 is a sectional view showing a construction for electrically driving an inspection
glass frame adaptor to an attached position and a detached position of a sandwiching
member.
Figs. 19(a) and 19(b) are schematic views illustrating a function to detect based
on projection images in CCDs (light detectors) whether the inspection glass frame
adaptors are fitted or not.
Figs. 20(a) and 20(b) are figures illustrating another detecting construction to detect
whether the inspection glass frame adaptors are fitted or not.
Fig. 21 is a perspective view showing an eye glass unit sandwiching members in the
conventional lens meter.
Fig. 22 is a plane view illustrating a state in which the inspection lens unit is
set to the lens meter shown in Fig. 21.
[Best Modes to Carrying Out the Invention]
[0020] In the following, best modes of the lens meter according to the present invention
will be explained with reference to the drawings. Fig. 1A is a perspective view overviewing
a general construction of a lens meter 100 as one embodiment of the present invention.
Fig. 1B illustrates optical systems, etc. built in the lens meter shown in Fig. 1A
by way of example.
(Construction)
[0021] The lens meter 100 shown comprises a casing 4 having a fallen cup-like section as
a whole as viewed from a side direction. The casing 4 comprises an upper casing body
1, a lower casing body 2 and a rear casing body 3. The upper casing body 1 has, at
its front face, a monitor 5 for displaying measured results of optical characteristics
and various operating switches 6 as shown in Figs. 1(A), and Figs. 2 and 3.
[0022] Between the upper casing body 1 and the lower casing body 2 is provided a setting
section 20 (eye glass support) at which an eye glass unit 16 (See Fig. 5) of which
optical characteristics are to be measured. Inside the upper casing body 1 are provided
light sources 7a, 8a such as LEDs and light-projecting optical systems 7b and 8b.
The light sources 7a, 8a emit inspection lights correspondingly to right and left
lenses of the eye glass unit 16 supported at the setting section 20. The light-projecting
optical systems 7b and 8b project the inspection lights emitted from the light sources
7a and 8a almost along optical axes 18a, 18a of the lenses 18, 18, respectively. The
light sources 7a and 8a may be partially or entirely arranged in the rear casing body
3, and a part of the light-projecting optical systems 7b and 8b may be provided in
the rear casing body 3.
[0023] Inside the upper casing body 1 are provided 2-stage lift type light-shielding members
53 and 54 each having a rectangular section as shown with broken lines along lower
inner peripheral portions of a front face and opposite side faces of the upper casing
body 1.
[0024] Inside the lower casing body 2 and the rear casing body 3 are provided CCDs 7d and
8d (light detectors, in this embodiment, a common CCD being used for 7d and 8d), detecting
optical systems 7c and 8c including Hartmann pattern plates, respectively, and controller
9. The CCD has two-dimensional spatial resolution. The Hartmann pattern plates lead
inspection lights of the inspection lights passing through lenses 18 and 18 of the
eye glass unit 16 supported at the setting section 20 to the respectively corresponding
CCDs 7d and 8d. The controller 9 performs various arithmetic processings for calculating
the optical characteristics of the lenses 18, 18 and controlling driving of various
parts based on light intensity distributions obtained by CCDs 7d and 8d, respectively.
A part of the inspecting optical systems 7c and 8c and a part or an entire part of
the CCDs 7d, 8d and the controller 9 may be provided in the rear casing body 3.
A pair of the lenses of the eye glass unit are accurately located along the optical
paths of a pair of right and left measuring optical systems positioned in right and
left portions of the apparatus body, respectively. The measuring optical system comprises
a light-projecting optical system (illuminating optical system) housed in the upper
casing body and a light-receiving optical systems housing in the lower casing body.
The left light-receiving optical system comprises LEDs 7a1 and 7a2, collimator
lenses 7b1 and 7b2, and a dichroic mirror 7b3. The LED 7a1 emits infrared light, and
LED 7a2 emits red light (wavelength: 630 nm). The dichroic mirror 7b3 reflects the
infrared light, and transmits the red light. The collimator lenses 7b1 and 7b2 convert
the spreading light fluxes from the LEDs 7a1 and 7a2 to parallel light fluxes as the
inspection lights, respectively.
The left light-receiving optical system comprises a Hartmann pattern plate 7c1,
a field lens 7c2 having a screen face 7c2', reflecting mirrors 7c3, 7c3', an optical
path synthesis prism 7c4, an image-forming lens 7c5 and a CCD (light-receiving element,
light receiver) 7d as an image-forming element. The pattern plate 7c1 has a number
of light-transmitting portions (not shown) in a matrix-shaped manner. The light-transmitting
portions may be through-holes or an array of numerous lenses. By this construction,
the pattern plate 7c1 can divide the measuring light flux into a number of discrete
measuring light fluxes.
The axis of a lens-receiving axis of an eye glass unit-supporting mechanism mentioned
later is set parallel to the measuring optical axis of the measuring optical system.
The right measuring optical system comprises a light-projecting optical system
(illuminating optical system) housed in the upper casing body and a light-receiving
optical systems housing in the lower casing body.
The light-receiving optical system comprises LEDs 8a1 and 8a2, collimator lenses
8b1 and 8b2, and a dichroic mirror 8b3. The LED 8a1 emits infrared light, and LED
8a2 emits red light (wavelength: 630 nm). The dichroic mirror 8b3 reflects the infrared
light, and transmits the red light. The collimator lenses 8b1 and 8b2 convert the
spreading light flux from the LEDs 8a1 and 8a2 to parallel light fluxes as measuring
light fluxes, respectively.
The right light-receiving optical system comprises a Hartmann pattern plate 8c1,
a field lens 8c2 having a screen face 8c2', a reflecting mirror 8c3, an optical path
synthesis prism 8c4, an image-forming lens 8c5 and a CCD (common CCD for the left
measuring optical system) 8d. The pattern plate 8c1 has a number of light-transmitting
portions (not shown) in a matrix-shaped manner. The light-transmitting portions may
be through-holes or an array of numerous lenses. By this construction, the pattern
plate 8c1 can divide the measuring light flux into number of discrete measuring light
fluxes.
The axis of a lens-receiving axis of an eye glass unit-supporting mechanism mentioned
later is set parallel to the measuring optical axis of the measuring optical system.
Since the common CCD (7d, 8d) is used as light-receiving elements of the right and
left measuring optical systems, the refractive characteristics of the right and left
lenses of the eye glass unit can be almost simultaneously measured by a smaller number
of the optical parts.
Further, according to this embodiment, the common CCD is employed as the light-receiving
elements for the right and left measuring optical systems, but independent CCDs may
be separately provided for the right and left measuring optical systems, respectively.
In this case, the refractive characteristics of the right and left lenses of the eye
glass unit can be completely simultaneously measured.
(Control circuit)
[0025] Further, outputs from the CCD 7d(8d) are led to an arithmetic control circuit 9,
and outputs from this arithmetic control circuit 9 is led to a control apparatus CPU
(personal computer). An operation lever (not shown) is provided at a side wall of
the casing 4, and a sensor (not shown) is provided to detect whether or not the operation
lever is pulled down horizontally so that outputs from the sensor may be inputted
into the arithmetic control circuit 9.
[0026] As shown in a detailed perspective view of Fig. 4, two sandwiching members 21, 22
are arranged apart from each other at front and rear sides of the lens meter 100,
respectively. Two sandwiching members 21 and 22 are displaceable nearer to or farther
from each other. As shown in Fig. 5 and Figs. 6(a) and 6(b) in section, an eye glass
unit 16 can be almost horizontally disposed between both the sandwiching members 21
and 22 (the optical axis of each of lenses 18 being directed in vertical directions
against a paper).
[0027] Two sandwiching members 21 and 22 are connected together by means of a connecting
member (not shown) so that they may be displaced simultaneously in opposite directions
and by almost the same displacing amount, interlocking with each other. Therefore,
the middle point between both the sandwiching members 21 and 22 is always kept constant
as viewed in front and rear directions irrespective of whether the space between the
sandwiching members 21 and 22 is narrow or wide. A known connecting mechanism as described
in detail in JP-A 2003-194670, etc. can be used as a connecting mechanism for the
sandwiching members 21 and 22 by this connecting member.
As the connecting member, one shown by a reference numeral 40 (40a, 40b) in Figs.
6 and 7 of U.S.P. 6,778,264A2 may be used.
[0028] Supporting pins 23 and 23 are erected at a setting section 20 to face lower surfaces
(those surfaces of the lenses which are directed to a human face when a person wears
the eye glass unit) of the respective lenses 18 when the eye glass unit 16 is set.
The supporting pins 23 and 23 receive the right and left lenses 18, 18 of the eye
glass unit 16 from their lower face sides, respectively. The supporting pins 23 and
23 are arranged in almost middle points between both the sandwiching members 21 and
22 as viewed in the front and rear directions.
[0029] The supporting pins 23 and 23 are provided at locations corresponding to centers
of detecting zones of the two CCDs 7d and 8d (in this embodiment, the common CCD being
used) arranged for the left and right lenses, respectively.
[0030] As viewed in Figs. 5 and 7, the width of a lower side portion of a frame 17 for the
lenses 18 of the eye glass unit 16 is almost equal to that of an upper side portion
of the frame 17 for the lenses 18. Thus, the optical axes of the lenses 18, 18 of
the eye glass unit 16 are almost in conformity with the locations of the two corresponding
pins 23 and 23, respectively, as viewed in the front and rear directions, in the state
that the eye glass unit 16 is sandwiched between the sandwiching members 21 and 22
as shown in Fig. 7. In other words, the positional relationship between the sandwiching
members 21, 22 and the supporting pins 23, 23 is so set that the optical axes 18a
and 18a of the lenses 18 and 18 of the eye glass unit 16 may be located on a line
connecting the two supporting pins 23, 23.
[0031] In addition, since the supporting pins 23 and 23 are arranged corresponding to almost
the centers of the detecting zones of the CCDs 7d and 8d, respectively, transmitted
lights passing the respective lenses 18 and 18 of the eye glass unit 16 enter almost
the centers of the respective detecting zones of the corresponding CCDs 7d and 8d.
Two sandwiching members 21 and 22 appropriately automatically locate the eye glass
unit 16 as viewed in the front and rear directions at the setting section 20.
[0032] Frame supports 25 and 26 each having a reverse L-letter shape are arranged at oppositely
outer sides of the sandwiching members 21 and 22, extending almost orthogonally to
the sandwiching members 21 and 22. The frame supports 25 and 26 are moved up and down
between a position where the upper faces 25a and 26a are positioned higher than the
tops of the supporting pins 23 and 23 and a position where the upper faces 25a and
26a are positioned not higher than the tops of the supporting pins 23 and 23. The
frame supports are urged to the position, by means of springs 65 (See Figs. 11(a)
and 11(b)) mentioned later, where the upper faces 25a and 26a are positioned higher
than the tops of the supporting pins 23 and 23.
[0033] As shown in Figs. 5 and Fig. 6(b), the frame 17 of the eye glass unit 16 to be measured
is placed on the upper faces 25a and 26a of the frame supports 25 and 26. At that
time, at least two portions of the frame 17 contact each of the upper faces 25a and
26a of the frame supports 25 and 26 for the left and right lenses 18, 18, respectively.
Thus, the eye glass unit 16 is supported at totally at least four points on the frame
supports 25 and 26, so that the setting posture of the eye glass unit 16 can be maintained
in a stabilized state.
[0034] Between the sandwiching members 21 and 22 is arranged a nose pad-supporting member
24 at almost a central portion as viewed in a lateral direction. The nose pad-supporting
member 24 has a circular arc-sectional peripheral face at a side opposed to the front
sandwiching member 21. The nose pad-supporting member 24 is slidable from almost the
central position illustrated as viewed in the front and rear directions, i.e., in
a longitudinal direction, to a rear side. The supporting member 24 is urged to the
position shown by a spring not shown. As shown in Fig. 7, when the sandwiching members
21 and 22 sandwich the eye glass unit 16 in cooperation with each other from the front
and rear sides, respectively, the cylindrical arc-shaped peripheral face of the nose
pad-supporting member 24 contacts nose pads 19 and 19 of the eye glass unit 16 and
presses the nose pads corresponding to the urging force.
[0035] At that time, since the posture of the eye glass unit 16 is autonomously changed
so that the pressing forces upon the right and left nose pads 19, 19 may be uniform.
Ultimately, the right and left portion contacts are stably set at positions apart
from the center of the setting section 20 by distance L1, L1 as viewed in right and
left directions, so that eye glass unit 16 is automatically centered at the setting
section 20 in the lateral direction.
[0036] The urging force of the nose pad-supporting member 24 is set smaller than a rearward
pressing force of the front sandwiching member 21 upon the eye glass unit 16, so that
the nose pad-supporting member 24 is pushed back with the pressing force of the front
sandwiching member 21 received via the right and left nose pads 19, 19 of the eye
glass unit 16.
[0037] On the other hand, as shown in Fig. 4, cylindrical members 27 and 28 which can turn
in directions shown by arrows, respectively, are provided inside the rear casing body
3, and rotary arms 29 and 30 each having an almost reversed L-letter shape and extending
upwardly and being bent toward the front side as shown in Fig. 4 are joined to the
cylindrical members 27 and 28, respectively. Near front tips of the rotary arms 29
and 30 are formed a pair of push pins 31a and 31b and a pair of 32a and 32b which
extend horizontally and project toward the opposed rotary arms 29 and 30, respectively.
[0038] When the cylindrical members 27 and 28 are turned as shown by the arrows, respectively,
the rotary arms 29 and 30 connected to the cylindrical arc members are turned, respectively.
Consequently, two pairs of the push pins 31a, 31b and 32a, 32b are butted against
the respective lenses 18, 18 of the eye glass lens 16 arranged above the support pins
23 and 23, so that the push pins push the lenses 18, 18 downwardly (strictly speaking,
in an arc direction tangentially downwardly) against the urging forces of the frame
supports 25, 26.
[0039] As shown in Fig. 8 in section, turning of the cylindrical members 27 and 28 is stopped
in the state that the lenses 18, 18 are sandwiched by the support pins at the under
side of the lenses and the push pins 31a, 31b, 32a, 32b at the upper side of the lenses,
thereby definitely vertically locating the lenses 18, 18.
[0040] When the push pins 31a, 31b, 32a, 32b push the lenses 18, 18 downwardly, the frame
supports 25 and 26 receive downward press forces via the frame 17 of the eye glass
unit 16. Thereby, the frame supports are downwardly pushed down by the length of a
gap existing primarily between the lower faces of the lenses 18 and the support pins
23.
[0041] As mentioned above, the setting section 20 is designed such that the eye glass unit
16 is set (or supported) at a given measuring position with respect to the vertical
direction, the lateral directions and the longitudinal direction.
[0042] As shown in Fig. 10(a) in section, that length area of the frame support 26 where
the frame 17 of the eye glass unit 16 is not disposed (a portion near a line C-C in
Fig. 5, for example) has an almost inversed L-letter sectional shape. As shown in
Fig. 10(b) in section, that length area of the frame support 26 where the frame 17
of the eye glass unit 16 may be disposed (a portion around a line D-D in Fig. 5),
a notch 26b which penetrates the frame support 26 is formed at a corner of the almost
L-letter shape section. Although not shown, a same notch is formed in the other frame
support 25.
[0043] Since an outermost portion of each of the frame supports 25, 26 is cut out in such
a manner, this prevents an incident that if an eye glass unit 16 having a narrow width
between right and left hangers is to be measured, one of the hangers, not the frame
of the eye glass unit 16, would ride over the frame support 25 or 26 and thereby the
eye glass unit 16 would be set inclinedly. Thus, even such an eye glass unit having
the narrow width between the hangers can be disposed on the setting section in a correct
posture.
[0044] Further, as shown in Fig 10(b), a frameless eye glass unit comprises lenses 18 and
hangers 17a connected together by means of connecting pins 17b. The connecting pins
17b pass the respective lenses 18, and projects toward the frame supports 25, 26.
In addition, since the connecting pins 17b are attached to the respective lenses 18,
the pins are located at widthwise inner sides than the right and left outer sides
of the framed eye glass unit. Therefore, the hanger is likely to ride over the frame
support 25 or 26. If the connecting pin 17b rides over the frame support 25 or 26,
it may be that the eye glass unit is inclinedly supported or that the supporting position
of the eye glass unit is deviated by the downward pressure from the pressing pins
31a, 31b, 32a, 32b.
[0045] However, since the notch 26b is formed in the above manner, the connecting pin 17b
enters the notch 26b. This prevents the incident that the eye glass unit 16 is inclinedly
set in the state that the connecting pin 17b rides over the frame support 25 or 26.
Accordingly, the eye glass unit can be disposed in an appropriate posture.
[0046] If the width W1 of the lower casing body 2 in the lateral direction is sufficiently
made smaller than that W2 of the eye glass lens, the same effect as in the case that
the width between the frame supports 25 and 26 is set narrower and the notches 25b
and 26b are formed can be obtained. On the other hand, since the CCDs 7d and 8d extending
two-dimensionally are arranged in the lower casing body 2, the detecting areas of
the CCDs 7d and 8d become narrower, so that spatial resolution of the measuring results
may be deteriorated.
[0047] Therefore, the formation of the above-mentioned notches 25b and 26b can stabilize
the eye glass unit 16 without narrowing the detecting areas of CCD 7d, 8d, i.e., reducing
the spatial resolution of the measured results.
[0048] Next, a lift mechanism of two-stage lift type light-shielding members 53 and 54 provided
in the upper casing body 1 will be explained with reference to the sectional views
of a principal portion in Figs. 11(a) and 11(b) and Figs. 12(a) and 12(b).
[0049] First, inside the rear casing body 3 are arranged a feed screw 61, a vertically movable
nut 62, a lift base member 51, a swing member 52, a stopper plate 63, and a support
press-down member 64. The feed screw 61 extends vertically, and is turned upon receipt
of a driving force from a driver such as a motor not shown. A rear end 53a of the
first light-shielding member 53 mentioned later is joined to the lift base member
51. A rear end 54a of the second light-shielding member 54 is joined to a tip portion
52a of the swing member 52, and the rear end 52a is axially supported by the lift
base member 51. A rear portion 54a of the second light-shielding member 54 is joined
to a tip end 52b of the swing member 52. A rear end portion 52a of the swing member
52 is axially supported by the lift base member 51. A disposing portion 52e of the
swing member 52 contacts an upper face of the nut 62 due to its self weight. When
the lift base member 51 moves downwardly, a stopper plate 63 contacts a lower end
51b of the front wall 51c of the lift base member 51. One end (first end) 64a of the
support press-down member 64 contacts the lower face of the descended nut 62, and
the other end (second end) 64c contacts upper faces of rear end portions 25c and 26c
of the frame supports 25, 26. The support press-down member 64 turns around an axially
supporting portion 64b between opposite ends 64a and 64c as its rotary center.
[0050] The lift base member 51 is constructed such that it is movable up and down only along
a guide vertically extending (not shown), while maintaining its posture.
[0051] The swing member 52 passes an opening 51a formed in the front wall 51 of the lift
base member 51. The swing member 52 can be vertically swung around a rear end 52a
portion as its turning center between upper and lower edges of the opening 51a.
[0052] Further, since the outer periphery of the nut 62 would interfere with front wall
51c and side wall of the lift base member 51, etc. during rotation, the nut is made
vertically movable relative to the feed screw 61 under rotation without turning together
with the feed nut 61.
[0053] A spring 65 is arranged on a lower face side of the rear end 25c, 26c of the frame
support 25, 26 for urging the frame support 25, 26 upwardly.
[0054] The first light-shielding member 53 formed in a cup-like sectional shape is arranged
inside the upper casing body 1, while extending along the inner periphery of the upper
casing body 1. Further, the second light-shielding member 54 having a cup-like sectional
shape is arranged inside the first light-shielding member 53.
[0055] As shown in Figs. 1A and 11(a), each of the light-shielding members 53 and 54 is
housed in the upper casing body 1 and is not seen from outside except a measuring
time period in which the light characteristics of the lenses 18 of the eye glass unit
16 are measured.
[0056] One other hand, the light-shielding members are descended from the lower end 1a of
the upper casing body 1 during the time period for measuring the optical characteristics
of the lenses 18, so that they cover around an upper space of the eye glass unit 16
set at the setting section 20 and suppress external side light (noise light) from
entering the glasses 18 of the eye glass unit 16.
[0057] Next, up and down movement of the light-shielding members 53, 54 with the lift mechanism
and the up and down movement of the frame supports 25, 26 will be explained.
[0058] First, as shown in Fig. 11(a), the nut 62 is positioned at an upper portion of the
feed screw 61. The upper face of the nut 62 A contacts the disposing portion 52e of
the swing portion 52, thereby supporting the swing member 52 from the lower side.
Further, since the rear end 52a of the swing member 52 is axially supported by the
lift base member 51, the supporting force received from the nut 62 functions as a
rotary moment in a clockwise rotating direction upon the lift base member 51. As a
result, the upper face 52d of the swing member 52 ahead of the disposing portion 52e
contacts the upper edge of the opening 51a formed in the front wall 51c of the lift
base member 51 to upwardly press the upper edge of the opening 51a.
[0059] Since the lift base member 51 is movable only vertically without changing its posture,
a portion of the lift base member 51 that axially supports the rear end portion 52a
of the swing member 52 and the upper edge of the opening 51a are upwardly pushed.
Thus, the lift base member 51 is supported by the nut 62 via the swing member 52.
[0060] The first light-shielding member 53 connected to the lift base member 51 and the
second light-shielding member 54 connected to the swing member 52 are housed in the
upper casing body 1, while being located above the lower edge 1a of the upper casing
body 1.
[0061] Next, when the feed screw 61 is turned in a given direction by a driver not shown,
the nut 62 is descended as shown in Fig. 11(b). As the nut 62 is descended, the lift
base member 51 and the swing member 52 are lowered without changing the relatively
positional relationship between the members 51 and 52.
[0062] Thereby, the first light-shielding member 53 connected to the lift base member 51
is descended in parallel, so that the member 53 projects downwardly from the lower
edge 1a of the upper casing body 1. The second light-shielding member 54 is located
above the lower edge 1a of the upper casing body 1, and housed inside the upper casing
1.
[0063] When the lower end 51b of the front wall 51c of the lift base member 51 is lowered
to a position where the lower end 51b contacts the stopper plate 63, lowering of lift
base member 51 is stopped (Fig. 11(b)).
[0064] When the nut 62 is lowered from this state by turning the feed screw 61, as shown
in Fig. 12(a), the disposing portion 52e of the swing member 52 is lowered due to
the self weight of the swing member 52 as the nut 62 is lowered, whereas the rear
end portion 52a as the axially supported portion with the lift base member 51 which
stops descending is not lowered. Consequently, the swing member 52 turns around the
rear end portion 52a as its rotary center counterclockwise as shown. At that time,
the swing member 52 is turned until its lower edge 52c contacts the lower edge of
the opening 51a of the lift base member 51.
[0065] By this, the second light-shielding member 54 connected to the swing member 52 is
turned together with the swing member 52, and projects from the lower edge 53a of
the first light-shielding member 53.
[0066] By the above operation, the two-stage lift type light-shielding members 53 and 54
are successively projected, and the projected light-receiving members 53 and 54 shield
external light from entering the upper space of the eye glass unit 16 set at the setting
section 20 from the side direction.
[0067] Since the second light-shielding member 54 is down only to a position just beside
the eye glass unit 16, the light-shielding member 54 does not completely cover the
upper space of the eye glass unit 16. The light fluxes led to the CCD 7d, 8d by the
light-detecting optical systems 7c and 8c disposed inside the lower casing body 2
are limited to those in a given incident angle range. As a result, light shielding
with the light-shielding members 53 and 54 can shield external light having a relatively
small incident angle with respect to the lens 18 of the eye glass unit 16 (angle with
respect to the optical axis). Thereby, the external light-shielding function can be
sufficiently attained.
[0068] Further, the second light-shielding member 54 is only placed on the upper face of
the nut 62 via the swing member 52, and is descended merely due to the self weights
of the second light shielding member 54 and the swing member 52. Since the shielding
member is not pushed down by driving force of a driver, the second light-shielding
member 54 can be easily pushed up even in the descending state (Fig. 12(a)) by pressing
up the member 54 with a load greater than the self weights of the second light-shielding
member 54 and the swing member 52 from the lower side.
[0069] The first shielding member 53 is merely disposed on the upper face of the nut 62
via the lift base member 51 and the swing member 52, and is lowered merely by the
self weights of the first light-shielding member 53, the lift base member 51, the
swing member 52 and the second light-shielding member 54. Since the first light-shielding
member 53 is not pushed down by driving force of a driver, the first light-shielding
member 53 can be easily pushed up even in the descending state (Fig. 12(a)) by pressing
up the member 53 with a load greater than the total self weight of the above from
the lower side.
[0070] Therefore, even if a finger or the like of an operator enters the descending zone
of the light-shielding members 53 and 54 through operator's erroneous action, no forcedly
descending load is applied to the light-shielding members 53 and 54 at a location
other than the place where the light-shielding members 53 and 54 are butted to the
finger or the like.
[0071] When the nut 62 is descended from the above state by further turning the feed screw
61, as shown in Fig. 12(b), the lower face of the nut 62 pushes down the first end
portion 64a of the support push-down member 64. Consequently, the support push-down
member 64 is turned around the axially supported portion 64a as its rotary center,
and the second end portion 64c presses down the upper face 25c, 26c of the frame support
25, 26 against the urging force of the spring 65, thereby descending the frame support
25, 26.
[0072] In the above, the descending operation of the light-shielding members 53 and 54 and
the descending operation of the frame supports 25, 26 with the lift mechanism are
explained. The ascending operation can be performed through successively reversely
effecting the above descending operation by reversely turning the feed screw 61 with
the driver from the position shown in Fig. 12(b).
[0073] Figs. 14(a) and 14(b) are perspective views showing trial frame adaptors (inspection
glass frame adaptors) 80, 70, respectively, which are used when optical characteristics
of an inspection glass unit 10 in which the detachable lenses 12 shown in Fig. 13(b)
are fitted to the trial frame 11 (inspection glass frame) shown in Fig. 13(a).
[0074] As shown in Fig. 15, the adaptor 80 of Fig. 14(a) is placed over the rear sandwiching
member 22 at the setting section 20 from an upper side, whereas the adaptor 70 of
Fig. 14(b) is placed over the front sandwiching member 21 at the setting section 20
from the upper side. Each of the adaptors is uniquely located through being engaged
with a part of a contour shape of the corresponding sandwiching member 21, 22 as viewed
in a plane.
[0075] That is, the adaptor 80 is so designed that an inner face 84a of a rear wall 84 almost
contacts a rear face (a back face opposed to a face facing the other sandwiching member
21) of the rear sandwiching member 22, whereas an inner face 83a of a front central
wall 83 contacts a recessed face formed in a central portion of a front face (the
face opposed to the other sandwiching member 21) of the rear sandwiching member 22.
[0076] Similarly, the adaptor 70 is so designed that an inner face 73a of a front wall 73
almost contacts a front face (a face opposed to another facing the other sandwiching
member 22) of the front sandwiching member 21, whereas an inner face 72a of a rear
wall 72 contacts a recessed face formed in a central portion of a rear face (a face
opposed to the other sandwiching member 21) of the front sandwiching member 21.
[0077] When the adaptors 70 and 80 are fitted to the respective sandwiching members 21 and
22, the adaptors project oppositely toward the respectively opposed sandwiching members
21 and 22. The adaptors 70 and 80 have projecting sandwiching portions 71 and 81 and
82, respectively, which are to be butted against those portions of the trial frame
11 which are other than the movable ranges of the tabs 12c of the detachable lenses
12 projecting from the trial frame 11 of the inspection glass unit 10 supported as
the glass unit. The other portions of the adaptors than the projecting sandwiching
portions 71, 81 and 82 are designed to not interfere with the movable ranges of the
tabs 12c.
[0078] That is, more specifically, as shown in the plane view of Fig. 16, the projecting
sandwiching portion 71 of the adaptor 70 contacts almost a central portion of a lateral
connecting portion 11b of the trial frame 11, whereas the projecting sandwiched portions
81 and 82 of the adaptor 80 contact right and left lower edges of the trial frame
11 other than the movable ranges of the tabs 12c.
[0079] The projecting length L3 of the projecting sandwiching portion 71 of the adaptor
70 from the central portion of the rear side of the front sandwiching member 21 and
the projecting length L2 of the projecting sandwiching portions 81 and 82 of the adaptor
80 from the projected front face of the rear sandwiching member 22 are set such that
when the sandwiching members 21 and 22 are displaced by the same distance of L4 in
the opposite directions, interlocking with each other, the optical axes 12d, 12d of
the lenses 12, 12 of the inspection glass unit 10 sandwiched by the projecting sandwiching
portions 71, 81 and 82 may be aligned on a straight line connecting the support pins
23, 23.
[0080] As a result, the transmitted lights passing the optical axes 12d, 12d of the respective
lenses 12, 12 of the inspection glass unit 10 enter almost the centers of the detecting
zones of the corresponding CCDs 7d, 8d, respectively (In this embodiment, the common
CCD is used as the CCDs 7d and 8d). The inspection glass unit 10 is automatically
and appropriately located in the front and rear, i.e., longitudinal direction.
[0081] Since the adaptors 70, 80 are each formed almost in an inversed cup-like sectional
shape when cut by a plane orthogonal to a longitudinal direction thereof, they can
be fitted to the respective sandwiching members by simple operations that the adaptors
70 and 80 are placed over the sandwiching members 21 and 22 each having almost a quadric
prism-like shape from their upper sides, respectively. The adaptors 70 and 80 can
be detached from the sandwiching members 21 and 22, respectively, by simple operations
that the former are pulled upwardly from the latter, respectively.
(Function)
[0082] Next, the function of the lens meter 100 according to the present embodiment will
be explained.
[0083] First, the function will be explained in the case that the optical characteristics
of the ordinary eye glass unit product 16 are measured. As shown in Fig. 4, the lens
meter 100 is so set in the primary state that both the sandwiching members 21, 22
are set largely apart from each other, the frame supports 25, 26 are set urged upwardly,
the press pins 31a, 31b, 32a and 32b are set retracted upwardly, and the light-shielding
members 53 and 54 are housed inside,the upper casing 1 as shown in Fig. 11(a).
[0084] In this primary state, as shown in Fig. 5 and Fig. 6(a) and 6(b), the eye glass unit
16 is placed on the upper faces 25a and 26a of the frame supports 25 and 26, respectively,
between the sandwiching members 21 and 22.
[0085] Next, when a measuring-start order is inputted into the operation button 6, an order
input to the operation button 6 is inputted to the controller 9, which operates the
driver not shown to move the sandwiching members 21 and 22 interlocking with and approaching
to each other.
[0086] As shown in Fig. 5, the eye glass unit 16 which is first placed between the sandwiching
members 21 and 22 is sandwiched there between as shown in Fig 7, while contacting
the nose pad-supporting member 24. Thus, the eye glass unit 16 is set at an appropriate
measurement position as to the longitudinal direction and the lateral direction.
[0087] Then, the controller 9 drives a motor not shown to descend the light-shielding members
53 and 54 until positions shown in Fig. 12(a) by rotating the feed screw 61 of Fig.
11(a).
[0088] Parallel to the descending control of the light-shielding members 53 and 54, the
driver is controlled to turn the columnar members 27 and 28 (See Fig. 4), so that
the press pins 31a, 31b, 32a and 32b formed at the tips of the rotary arms 29 and
30, respectively, press down the lenses 18, 18, respectively until the lenses contact
the support pins 23, 23 (See Figs. 8(a) and 8(b)).
[0089] When the glasses are pressed down by the press pins 31a, 31b, 32a and 32b, the eye
glass unit 16 is downwardly displaced, while being kept sandwiched with the sandwiching
members 21 and 22. At that time, the frame 17 of the eye glass unit 16 slides on the
sandwiching members 21 and 22.
[0090] As the eye glass unit 16 is displaced downwardly, the frame supports 25 and 26 are
pressed and displaced down by a displaced distance of the eye glass unit 16.
[0091] Next, as shown in Fig. 12(b), when the nut 62 is further descended, the frame supports
25 and 26 are descended apart from the frame 17 of the eye glass unit 16.
[0092] The eye glass unit 16 is appropriately supported by the sandwiching members 21 and
22, the supporting pins 23, 23, and the press pins 31a, 31b, 32a and 32b. If non-uniform
sliding occurs at the sliding areas between the frame 17 of the eye glass unit 16
and the sandwiching members 21 and 22 when the push pins 31a, 31b, 32a and 32b press
down the lenses 18, 18, it may be that the eye glass unit 16 is inclinedly sandwiched,
resulting in inappropriate supporting that either one of the glasses floats from the
supporting pin 23.
[0093] Accordingly, the sandwiching members 21 and 22 are temporarily widened from the above
supporting state, and the glasses are temporarily supported by the supporting pins
23, 23 and the press pins 31a, 31b, 32a and 32b only.
[0094] By this, even if the eye glass lens 16 is not appropriately supported, its posture
is corrected to make the supporting pins 23, 23 and the press pins 31a, 31b, 32a and
32b appropriately contact the respective lenses 18, 18.
[0095] Thereafter, the sandwiching members 21 and 22 sandwich the eye glass unit 16 again,
and then the columnar members 27 and 28 are turned to retract the press pins 31a,
31b, 32a and 32b upwardly.
[0096] By the above function, as shown in Fig. 9, the eye glass unit 16 is supported at
appropriate measurement position and posture by the supporting pins 23, 23 and the
sandwiching members 21 and 22.
[0097] Next, the controller 9 makes the light sources 7a and 8a emit their inspection lights,
which are inputted to the respective lenses 18, 18 along their optical axes 18a, 18a
by the respective light-projecting systems 7b and 8b.
[0098] Then, the transmitted lights of the inspection lights through the respective lenses
18, 18 are projected on the CCDs 7d and 8d, respectively (In this embodiment, the
common CCD is used as the CCDs 7d and 8d).
[0099] Since the detecting optical systems 7c and 8c have their Hartmann plate, the transmitted
lights are inputted into the CCDs 7d and 8d as lights carrying information on optical
characteristics of small areas of the respective lenses 18, 18 and having two-dimensional
spatial resolution, various optical characteristic data of each of the lenses 18,
18 can be obtained when the controller 9 performs arithmetic processing of detected
light intensities of arrayed elements of the CCDs 7d, 8d.
[0100] At that time, the positional relationship is set such that the transmitted lights
passing the optical axes 18a, 18a of the lenses 18, 18 are inputted into almost the
centers of the CCDs 7d and 8d, respectively. Since portions of the lenses 18, 18 corresponding
to the optical axes 18a, 18a are supported by the supporting pins 23, 23, strictly
speaking, the transmitted lights passing the lenses 18, 18 along the optical axes
18a, 18a will not actually reach the CCDs 7d, 8d.
[0101] However, since data corresponding to such defect inspection points can be calculated
based on detection data at their respective surrounding areas by interpolation, the
defect inspection points pose no problem in obtaining the information on the optical
characteristics of the entire lenses.
[0102] As shown in Figs. 2 and 3, the thus obtained optical characteristic information is
displayed on the monitor 5 according to a given format.
[0103] After the measurement of the optical characteristics, the controller 9 controls the
driver to return the sandwiching members 21 and 22 to their initial positions, and
the feed screw 61 is reversely rotated to raise the frame supports 25, 26 and house
the light-shielding members 53 and 54 in the upper casing body 1.
[0104] Next, measurement of the optical characteristics of the inspection glass unit 10
shown in Figs. 13A and 13B will be explained. As shown in Fig. 4, the lens meter 100
is so set in the primary state similarly in the case of the measurement of the eye
glass unit product 16 that both the sandwiching members 21, 22 are set largely apart
from each other, the frame supports 25, 26 are set urged upwardly, the press pins
31a, 31b, 32a and 32b are set retracted upwardly, and the light-shielding members
53 and 54 are housed inside the upper casing 1 as shown in Fig. 11(a).
[0105] The trial frame adaptor 80 shown in Fig. 14(a) is placed over the rear sandwiching
member 22 such that its projecting sandwiching portions 81 and 82 project toward the
front sandwiching member 21, whereas the trial frame adaptor 70 shown in Fig. 14(b)
is placed over the front sandwiching member 21 such that its projecting sandwiching
portion 71 projects toward the rear sandwiching member 22.
[0106] Thereafter, the inspection lens unit 10 is placed on the upper faces 25a and 26a
of the frame supports 25 and 26 between the adaptors 70 and 80.
[0107] Then, when a measuring-start order is inputted into the operation button 6, an order
input to the operation button 6 is inputted to the controller 9, which operates the
driver not shown to move the sandwiching members 21 and 22 interlocking with and approaching
to each other.
[0108] As shown in Fig. 16, the inspection glass unit 10 placed between the adaptors 70,
80 is sandwiched by the projecting sandwiching portions 71, 81 and 82 of the adaptors
70 and 80, while being butted to the nose pad-supporting member 24. Thereby, the inspection
glass unit 10 is set to an appropriate measurement position, that is, the optical
axes 12d, 12d of the detachable lenses 12, 12 of the inspection glass unit 10 are
set on a straight line connecting the supporting pins 23, 23.
[0109] Subsequent operation is similar to the case where the ordinary eye glass unit 16
is measured, and therefore its explanation will be omitted.
[0110] As mentioned above, according to the lens meter 100 of this embodiment, when the
optical characteristics of the detachable lenses 12, 12 fitted to the inspection glass
unit 10 are to be measured, the trial frame adaptors 70 and 80 are fitted to the sandwiching
members 21 and 22, respectively, so that the projecting sandwiching portions 71, 81
and 82 of the adaptors 70 and 80 can sandwich and hold the trial frame 11 of the inspection
glass unit 10.
[0111] In addition, since the adaptors 70 and 80 do not interfere with the movable ranges
of the tabs 12c, 12c of the detachable lenses 12, 12 fitted to the inspection glass
unit 10, the detachable lenses will not be turned or displaced when the inspection
glass unit 10 is sandwiched with the adaptors 70 and 80. Accordingly, the optical
characteristics of the detachable lenses 12, 12 can be measured at high precision,
while maintaining the positional relationship between the trial frame 11 attained
when the inspection glass unit 10 is first set at the setting portion.
[0112] Further, since the adaptors 70 and 80 do not contact the tabs 12c and 12c, the optical
axes 12d, 12d of the detachable lenses 12, 12 of the inspection glass unit 10 are
not set at positions largely deviated from almost the centers of the CCDs 7d and 8d,
respectively. From this point of view, measurement results can be obtained at high
precision.
[0113] Further, since the adaptors 70 and 80 are fitted to the sandwiching members 21 and
22, respectively, not to the inspection glass unit 10, the adaptors can be fitted
more easily as compared with a case where such adaptors are fitted to the inspection
glass unit 10.
[0114] In the lens meter 100 of this embodiment, the inspection glass frame adaptors 70
and 80 are separately formed from the sandwiching members 21 and 22, and detachably
fitted to the sandwiching members 21 and 22, respectively. This is contrived based
on the following effects.
[0115] That is, if it is frequently required to exchange a case where the optical characteristics
of the detachable lenses 12, 12 of the inspection glass units 10 are to be measured
and a case where the optical characteristics of lenses of the lenses 18, 18 of ordinary
eye glass units 16 are to be measured, it is preferable from the standpoint of easy
operation that the adaptors 70 and 80 are preliminarily slidably or turnably attached
to the sandwiching members 21 and 22, respectively, and the adaptors 70 and 80 are
slid or moved to be fitted to or detached from the actually sandwiching portions of
the sandwiching members 21 and 22. Generally, it is considered that the frequency
at which the ordinary eye glass units 16 are measured is far greater than that at
which the inspection glass units are measured and that the frequency of exchanging
in measurement between the ordinary eye glass units 16 and the inspection glass units
10 is very low. In such a case, the adaptors 70 and 80 will not impede the measurement
of the ordinary eye glass units 16, when the adaptors 70 and 80 are separately provided
from the sandwiching members 21 and 22 rather than the adaptors being preliminarily
attached to the sandwiching members.
[0116] The inspection glass frame adaptors in the lens meter according to the present invention
will not be limited to those 70 and 80 in this embodiment. The adaptors may be formed
integrally with the sandwiching members as parts of them, respectively, provided that
the adaptors are turned or displaced relative to main bodies of the sandwiching members
so that the adaptors may be fitted to or detached from the substantial sandwiching
faces of the sandwiching members, respectively.
[0117] That is, as shown in Figs. 17(a) and 17(b) as sectional views of sandwiching members
21 and 22 orthogonal to a longitudinal direction thereof, for example, one end of
each of the adaptors 70 and 80 each having an almost L-letter section may be turnably
axially supported on the upper face of the sandwiching member by a pin-connected hinge
(e.g., thin hinge) so that the adaptors 70 and 80 may be integrated with the sandwiching
members 21 and 22 and that the adaptors 70 and 80 may be turned around the hinge to
be fitted to the sandwiching faces of the sandwiching members 21 and 22 when needed
(Fig. 17(b)), whereas the adaptors 70 and 80 may be integrated with the sandwiching
members 21 and 22 and that the adaptors 70 and 80 may be turned around the hinge to
be detached from the sandwiching faces of the sandwiching members 21 and 22 when not
needed (Fig. 17(a)).
[0118] In this way, the adaptors 70 and 80 can be fitted to and detached from the sandwiching
faces of the main bodies of the adaptors 70 and 80, respectively in the state that
the adaptors 70 and 80 are kept integrated with the sandwiching members 21 and 22,
respectively. Thus, accidental loss of the adaptors 70 and 80 can be prevented.
[0119] Further, when the lens meter has the adaptors 70 and 80 integrated with the sandwiching
members 21 and 22 in this way, the fitting and detaching operations of the adaptors
70 and 80 can be carried out by a driver such as electric motor.
[0120] That is, as shown in Fig. 18, for example, a gear 75 is attached to the hinge portion
for the adaptor 70, and a driven gear 96 which meshes with the gear 75 and an electric
motor 95 to turn the driven gear 96 are provided in the sandwiching member 21 with
which the adaptor 70 is integrated. The driving of the electric motor 95 is controlled
with the controller 9.
[0121] According to the thus constructed lens meter 100, if a mode in which the inspection
glass unit 10 is to be measured is selected by the operation button 6 provided at
the front face of the lens meter 100, the controller 9 controls and drives the electric
motor 95, which turns the electric motor 95 in a given rotary direction. Consequently,
the electric motor 95 drives the driven gear 96 in a direction shown by an arrow shown,
so that the gear 75 of the gear 70 meshing with the driven gear 96 is turned in an
arrow direction shown to fit the adaptor 70 to the sandwiching face side of the sandwiching
member 21.
[0122] On the other hand, when a mode in which the ordinary eye glass unit 16 is to be measured
is selected, the electric motor 95 is controlled and turned in a direction reverse
to one mentioned above, so that the adaptor 70 is detached from the sandwiching face
side of the sandwiching member 21.
[0123] Fig. 18 shows only the adaptor 70 and the sandwiching member 21, but a similar construction
may be employed for the adaptor 80 and the sandwiching member 22.
[0124] Operating load upon the operator can be reduced, when the adaptors 70 and 80 are
electrically fitted to and detached from the sandwiching members 21 and 22 in this
way, respectively.
[0125] In the case of the lens meter in which the adaptors 70 and 80 are manually fitted
to and detached from the sandwiching members 21 and 22, it may be automatically detected
whether or not the adaptors 70 and 80 are fitted to the sandwiching members 21 and
22, respectively.
[0126] As shown in Figs 19(a) and 19(b), whether the adaptors 70 and 80 are not fitted to
the sandwiching members 21 and 22 (Fig. 19(a)) or the adaptors 70 and 80 are fitted
to the sandwiching members 21 and 22 (Fig. 19(b)) may be detected by discriminating
with the controller 9 with reference to contour shapes of the sandwiching members
21 and 22 or the adaptors 70 and 80 projected on the CCDs 7d and 8d before sandwiching
with the sandwiching members 21 and 22 (initial stage). Alternatively, as shown in
Figs. 20(a) and 20(b), an adaptor 70 is provided with a pawl 74 projecting toward
a sandwiching member 21 which has a slit 21a at an upper face to allow passage of
the pawl 74, a photo coupler 91, 92 is provided inside the sandwiching member 21 for
detecting if the pawl 74 is inserted through the slit 21a, and whether the adaptors
70 and 80 are not fitted to the sandwiching members 21 and 22 (shown by a solid line
in Fig. 20(a)) or the adaptors 70 and 80 are fitted to the sandwiching members 21
and 22 (shown by a chain double-dashed line in Fig. 20(b)) may be detected by discriminating
with the controller 9 based on detection signals from the photo coupler 91, 92.
[0127] Fig. 20 shows only the adaptor 70 and the sandwiching member 21, but a similar construction
may be employed for the adaptor 80 and the sandwiching member 22. Further, such an
automatic detecting mechanism may be employed irrespective of whether the adaptors
70 and 80 are separate from or integral with the sandwiching members 21 and 22, respectively.
[0128] Further, mistake regarding attachment and detachment of the adaptors 70 and 80 can
be suppressed by informing the operator of the detection result through displaying
in the monitor, etc. according to the controller 9, as to whether or not the adaptors
70 and 80 are fitted.
[0129] Further, in the case of the lens meter 100 in which the operation button is pushed
to enable the controller 9 to discriminate the measurement mode (inspection lens unit-measuring
mode) in which the adaptors 70 and 80 need to be fitted and the measurement mode (eye
glass unit product-measuring mode) in which the adaptors need not be fitted, it may
be that the controller 9 compares a discrimination result between the fitting case
and the non-fitting case corresponding to the measurement modes with a detection result
as to whether or not the adaptors 70 and 80 are fitted, and if the comparison result
is correct, the measurement start is controlled, i.e., the controller drives and controls
various drivers, whereas if the comparison result is not correct, the controller makes
the monitor 5 display a message requesting the adaptors 70 and 80 to be fitted or
detached corresponding to the measurement mode without starting the measurement.
[0130] In this way, the controller 9 automatically detects the fitting and non-fitting of
the adaptors 70 and 80, and thus mistake regarding the fitting and detaching of the
adaptors 70 and 80 relative to the sandwiching members can be prevented by calling
attention to the operator or by not commencing the measurement starting operation.